Abstract

Critical care constitutes a significant and growing proportion of the practice of
emergency medicine. Emergency department (ED) overcrowding in the USA represents an
emerging threat to patient safety and could have a significant impact on the critically
ill. This review describes the causes and effects of ED overcrowding; explores the
potential impact that ED overcrowding has on care of the critically ill ED patient;
and identifies possible solutions, focusing on ED based critical care.

Keywords:

Introduction

Critical care begins immediately upon recognition of the critically ill (or potentially
critically ill) patient, who has been defined as 'any patient who is physiologically
unstable, requiring constant and minute-to-minute titration of therapy according to
the evolution of the disease process' [1]. Therefore, the spectrum of critical care is not limited to the care that is provided
within the confines of the intensive care unit (ICU). Rather, critical care begins
(and is often necessitated) outside the ICU setting [2]. The nature of the illness rather than the location of the patient defines the need
for critical care [1]; therefore, critical care patients are best defined physiologically rather than geographically.
Outside the ICU and postoperative recovery rooms, critical care is most commonly provided
in the emergency department (ED) [3].

Critical care constitutes a significant and growing proportion of ED practice [4-6]. Studies conducted in urban US EDs have reported that more than 150 days of critical
care time are provided in an ED annually [5,6]. Many EDs have optimized their ability to deliver certain aspects of critical care
for very specific scenarios, such as trauma, acute cerebrovascular accidents, and
acute myocardial infarctions (AMIs). Although EDs are designed to provide emergent
stabilization and initial therapy for critically ill patients, most EDs do not have
ICU-level resources for optimal longitudinal critical care delivery (such as uninterrupted
1 : 1 nursing care, focused subspecialty expertise, and invasive hemodynamic monitoring).
Currently, the provision of critical care in the ED is increasing (in terms of both
frequency and duration), largely because of ED overcrowding [5,7].

This review describes the causes and effects of ED overcrowding in the USA; explores
the potential impact this has on the care of the critically ill ED patient; and identifies
possible solutions, focusing on innovations in ED based critical care.

Emergency department overcrowding

In order to meet the increasing need for emergency services, many US EDs are being
pushed to their maximum capacity. Although no strict definition exists, 'ED overcrowding'
refers to an extreme volume of patients in ED treatment areas, forcing the ED to operate
beyond its capacity [8]. This overcrowding is potentially associated with exceeding conventional nurse :
patient ratios, providing medical care in makeshift patient care areas (e.g. triage
areas and hallways), and diverting ambulances to other institutions [9]. Overcrowding usually leads to extremely long wait times, especially for those patients
who are not critically ill, which leads to patient dissatisfaction, patient walkouts,
and the potential for compromised medical care.

Although the exact incidence of ED overcrowding has not been studied in rigorous prospective
investigations, widespread ED overcrowding has been cited by survey studies in the
literature [10-14]. According to a 2001 report, 91% of US ED directors (525 out of 575 directors) reported
problematic crowding in their departments, and 39% reported overcrowding on a daily
basis [11]. A recent survey conducted by the American Hospital Association reported that the
percentage of large hospital EDs that are consistently operating 'at or above capacity'
has reached 90% [14]. In the lay press, numerous reports have documented breaches of patient safety because
of overcrowding, and these reports have questioned the ability of the entire US emergency
care system to provide safe care during the current surge in demand for emergency
services.

Causes

The causes of ED overcrowding are complex and multifactorial [15-17]. The primary determinants of ED overcrowding are not related to patient throughput
inside the ED but actually originate outside the ED [18]. Of these, the two most important determinants of ED overcrowding pertaining to the
critically ill are an increasing volume of high-acuity patients presenting to the
ED and insufficient inpatient capacity.

Between 1992 and 1999, ED visits rose 14% from 89.8 million to 102.8 million visits
annually, with the steepest gains in volume over the last 2 years of that time period
[19]. While this increase in patient volume took place in the 1990s, 1128 EDs closed their
doors [20]. As a result, more visits are being concentrated in fewer EDs. An increasing proportion
of these patients are high-acuity patients who require critical care. Lambe and coworkers
[7] reported a 59% increase in critically ill patients presenting to California EDs from
1990 to 1999. The increasing severity of illness among ED patients has been attributed
to age shifts in the population and a higher prevalence of patients with severe chronic
medical conditions. Considering the projected future growth in critically ill populations
as a whole [21], this trend toward increasing severity of illness among ED patients will probably
continue.

Although escalating patient acuity places a large strain on ED resources, the most
important cause of ED overcrowding is insufficient inpatient capacity for ED patients
who require hospital admission [8,22,23]. A lack of inpatient beds is also the most important contributor to ambulance diversion
[24]. The number of inpatient hospital beds in the USA has declined sharply over the past
2 decades. Between 1981 and 1999 the total number of inpatient beds decreased by 39%
[23]. This cutback has largely been the result of managed care initiatives and hospital
cost-containment strategies. Eliminating inpatient beds maximizes the hospital census
and ensures a 'full house' at all times, which is favorable from a financial standpoint
[9]. However, when hospitals are perpetually functioning at greater than 90% of their
inpatient capacity, they are ill equipped to handle surges in the number of admissions
[25]. The current US nursing shortage exacerbates the lack of inpatient capacity by further
decreasing the number of staffed beds available to offload an overcrowded ED.

Effects

Inadequate inpatient capacity for a patient population with increasing severity of
illness forces the ED to serve as a holding area for admitted patients. The term 'boarding'
refers to patients who are admitted to the hospital but who remain in the ED, sometimes
for more than 24 hours, because of the lack of available beds [8,18,26]. Critically ill patients are no exception because ICU patients may also board in
the ED for extraordinarily long periods until an ICU bed becomes available [4]. A recent report from the American Hospital Association [14] indicated that the average waiting time for an inpatient acute or critical care bed
in US EDs is more than 3 hours, but the average waiting time nearly doubles (5.8 hours)
in hospitals that consistently have ED overcrowding [14].

EDs are designed for rapid triage, stabilization, and initial treatment. When boarding
in the ED causes a 'gridlock', the ED becomes the site for ongoing (i.e. longitudinal)
care in the acute phase of hospitalization. In this scenario EDs must provide ongoing
care for critically ill patients, effectively serving as expandable extensions of
the ICU or 'de facto ICUs' [27]. However, EDs are not designed, equipped, or staffed to provide continuing care for
the critically ill patient. Although most EDs have specialized areas in which they
care for patients who present with trauma and AMI, most do not have the ability to
perform invasive hemodynamic monitoring, including arterial and pulmonary artery catheterization.
They are designed for rapid stabilization, including resuscitation from cardiac arrest
(i.e. 'code' situations), but not for extended care.

Conventional ED nurse : patient ratios do not typically allow for the focused attention
that a patient could receive in a critical care unit because most ED nurses are simultaneously
responsible for numerous patients with varying severities of illness. When a nurse
is assigned to an ICU patient boarding in the ED, one of two scenarios can be expected
to occur; either the ideal 1 : 1 or 1 : 2 critical care nurse : patient ratio will
be compromised, or the rest of the ED nursing staff will be required to absorb a greater
proportion of ED patients.

Boarding in the ED is not only reported to be a barrier to specialized inpatient care,
but it also has been identified as a potential high-risk environment for medical errors
[8]. Critically ill patients boarding in the ED are physically separated from the watchful
eye of the intensivists who are ultimately responsible for their care. All of these
factors could potentially lead to delays in recognizing deterioration in a patient's
condition and in initiating critical interventions, and may detract from optimal patient
care.

ED overcrowding has been reported to compromise patient safety, and the critically
ill are an especially vulnerable population and are at-risk for serious adverse events.
Although the impact of ED overcrowding on patient outcome has not yet been investigated
in rigorous prospective observational studies, survey studies in the literature have
linked ED overcrowding to clinically significant delays in diagnosis and treatment,
as well as to poor patient outcomes [10,15]. One report [10] linked ED overcrowding to delays in identification and treatment of time-sensitive
conditions, such as acute coronary syndrome, stroke, surgical emergencies, and septic
shock. ED overcrowding has also been shown to cause ambulance diversion and significant
delays in ambulance transport for patients with acute cardiac emergencies [28,29], regardless of the severity of illness [28]. A recent study reported that ED overcrowding was associated with delays in door-to-needle
time for AMI [30]. According to the Joint Commission on Accreditation of Healthcare Organizations [31], one half of all 'sentinel event' cases of poor outcomes that were attributable to
delays in therapy originated in the ED, with ED overcrowding playing a role in almost
one-third of these cases.

In addition to delays in therapy, ED overcrowding may also have an impact on the speed
at which critical illness is recognized, through ambulance diversion, triage delays,
and delays in bringing patients into treatment rooms. ED overcrowding may also result
in extraordinarily long waiting times, causing some patients to leave the ED without
being seen by a physician. Patients in the early hours of disease presentation who
are initially well appearing and triaged as 'nonemergent' have the potential to leave
the hospital without treatment and could become severely ill outside the hospital.

Boarding in the ED can subject critically ill patients to recognition and treatment
delays at a pivotal point in the hospital course when time-sensitive interventions
are necessary. Because optimal delivery of critical care in the early hours of disease
presentation is often time-sensitive (i.e. cardiogenic shock [32], hemodynamic optimization in severe sepsis [33,34], and the 'golden hour' of trauma [35,36]), impediments to prompt critical care recognition and delivery in the ED setting
could potentially represent a threat to patient safety.

Adding to the current landscape of ED critical care capacity is the potential threat
of terrorism and other disasters. The readiness of US EDs to care for critically ill
victims is a key element in preparedness for terrorism or bioterrorism. In a terrorist
attack with either conventional or biologic weapons, a large volume of patients would
be expected to require critical care services, including mechanical ventilation and
hemodynamic support [37]. Overcrowded EDs could be poorly prepared to handle mass casualty victims [16].

There is no simple solution to ED overcrowding. Opinion leaders have reported that
ED overcrowding will not be alleviated until hospitals adopt a multidisciplinary,
system wide approach focused on solutions to inpatient capacity constraints [18,27]. Strategic planning by hospital administration has been advocated by the Joint Commission
on Accreditation of Healthcare Organizations [38], including expedition of patient transfers out of critical care areas, anticipation
of delivery of care to patients who must be placed in temporary bed locations, and
incorporation of ED overcrowding initiatives into hospital performance improvement
goals. In addition, it has also been suggested that hospitals coordinate operating
room scheduling (for patients who are likely to need ICU care postoperatively) with
the anticipated cyclic patterns of increased ED patient visits, in which particular
days have predictably higher ED volumes. Operating room scheduling is an important
component of strategic planning for critical care needs and avoiding gridlock in the
hospital [39].

Despite these steps, ED boarding in the USA is unlikely to be significantly alleviated
in the near future. Thus, for any critically ill patient boarding in the ED, the ability
to recognize and deliver prompt ED based critical care may be crucial in ensuring
patient safety. In the era of ED boarding, innovative solutions are needed to provide
alternatives to the ongoing acute phase management of the critically ill. If critically
ill ED patients cannot be taken rapidly to the critical care unit, then it is necessary
to find new ways to take critical care to the patient [3]. This is the concept of 'critical care without walls' [2].

ED based critical care is not intended to be a substitute for conventional critical
care provided within the ICU, and neither is it intended to delay or hold a patient
in the ED any longer than is absolutely necessary. Critical care provided in the ED
would simply be a temporizing measure until an ICU bed becomes available. ED based
critical care requires an institutional commitment to ED infrastructure. The necessary
infrastructure would include the following components: a dedicated resuscitation area
in the ED; ability to perform basic hemodynamic monitoring (i.e. including but not
limited to measurements of central venous pressure, arterial blood pressure, and mixed
venous/central venous oximetry); mechanical ventilation capability, including dedicated
respiratory therapy staff; and a training program for ED nursing staff so that they
may develop proficiency in hemodynamic monitoring and mechanical ventilation. All
of these capabilities could be present in the Society for Academic Emergency Medicine's
vision for a 'level one' emergency center [40].

For an emergency physician, the perpetual task of maximizing patient throughput for
the entire ED is not compatible with the ongoing provision of comprehensive critical
care for an individual patient. Therefore, the physician coverage for critical care
patients boarding in the ED must be clearly defined. There are three different models
for expanding physician coverage in order to provide ongoing focused critical care
in the ED setting: the ICU-centric model, the ED-centric model, and the collaborative
ED–ICU model.

The ICU-centric model

In the ICU-centric model, the critical care consultant would take over responsibility
for any critically ill patient in the hospital at the time of patient identification,
regardless of location. This would include critically ill patients boarding in the
ED. Transfer of care would occur at the time of consultation, assuming that the patient
meets criteria for admission to the critical care service. This would best be accomplished
with an 'intensivist model' of staffing ICUs [41], in which a physician trained in multidisciplinary critical care is available around
the clock [42]. For patients boarding in the ED, the emergency physician would still be in close
proximity to respond to sudden major physiologic decompensations but they would not
be responsible for ongoing critical care. This would allow the emergency physician
to focus on patient throughput for the rest of the ED patients, and may also decrease
'hand-off' errors during patient transition because the intensivists would assume
control earlier in the patient's course.

The ED-centric model

In the ED-centric model, responsibilities for patient care would be site defined.
The ED physicians would take full responsibility for all critical care provided in
the ED, regardless of how long a patient may be boarding there. Responsibility for
patient care would not be transitioned to critical care staff until the patient arrives
in the ICU.

One example of this model is the early intervention team (EIT) at Henry Ford Hospital
(Detroit, MI, USA). Their ED-based EIT program was created to provide focused care
for critically ill patients (specifically severe sepsis patients) in the ED setting.
The EIT was founded on the principles that optimal delivery of critical care can be
time sensitive, and that aggressive ED based critical care interventions can rapidly
improve critical physiology and have a positive impact on outcome. The Department
of Emergency Medicine provides all of the EIT infrastructure (including additional
personnel, physician training, nursing training, physical plant modifications, and
critical care equipment) and maintains the program exclusive from all inpatient critical
care services. Essentially, they have built an acute-phase critical care unit in the
ED. The EIT physicians send the patient to the inpatient ICU after prospectively defined
end-points of resuscitation have been met. ED physicians (including resident physician
trainees) staff the program and provide ongoing focused critical care at the bedside,
allowing the other emergency physicians to focus on throughput for the noncritical
ED patients (Rivers EP, personal communication, 2004).

The collaborative model

During the transition of patient care from ED to ICU staff, the use of collaborative
evidence-based ED–ICU treatment protocols can help to facilitate uniformity of patient
care. The use of protocols to complement clinical decision making for the critically
ill has been shown to decrease unnecessary variations in clinical practice [43]. Protocol-directed care has already gained acceptance in the management of glycemic
control [44], sedation [45], and weaning from mechanical ventilation [46-48], but acute phase resuscitation can be guided by protocol as well [33,34]. Although applicable in all three models, collaborative protocols are more beneficial
in this model because there will probably be variability in clinical decision making
when patients are co-managed by two different teams of physicians. Collaborative protocols
may help to reduce transitional errors and to streamline care.

At our institution (Cooper University Hospital, Camden, NJ, USA), a collaborative
ED–ICU sepsis resuscitation protocol (an adaptation of the protocol described by Rivers
and coworkers [34]) was recently adopted as an institutional 'best practice' model. The ED staff is
responsible for patient identification and rapid protocol initiation. Per protocol,
the critical care physician is automatically consulted at the time of patient identification
for ongoing management. The protocol guides early resuscitative efforts in the ED
and carries over to the initial phase of the ICU course as patient care is transitioned
to the ICU team. Although transfer of patient care responsibilities (from ED to ICU
services) officially occurs at the time of critical care consultation, the ED physicians
continue to supervise protocol execution while the patient is boarding in the ED.
Before instituting the resuscitation protocol, we held in-service training for our
ED nursing staff and we trained all of our junior resident physicians in fundamental
critical care support [49]. In the future, protocol directed resuscitation might be applicable to shock profiles
other than sepsis. Conceptually, a collaborative ED–ICU model can facilitate a seamless
transition on the continuum of critical care, as envisioned by the late Dr Peter Safar
[50].

Conclusion

Critical care constitutes a significant and growing proportion of the practice of
emergency medicine. ED overcrowding (i.e. 'boarding' in the ED) can have an adverse
impact on patient safety, especially for the critically ill ED patient. Innovative
solutions are needed to provide optimal care for the ongoing acute phase management
of the critically ill in the ED setting.

Angus DC, Kelley MA, Schmitz RJ, White A, Popovich J Jr: Caring for the critically ill patient. Current and projected workforce requirements
for care of the critically ill and patients with pulmonary disease: can we meet the
requirements of an aging population?